3 of top 10 most polluted ZIP Codes in California are in L.A. County


If it’s any consolation to Southern California, none of its ZIP Codes claimed the top spot as the state’s most polluted, according to a California Environmental Protection Agency report.

That dubious distinction went to Fresno. But three of the 10 most pollution-heavy ZIP Codes were in Los Angeles County. The other seven, including Fresno, are in the San Joaquin Valley, according to the nation’s first comprehensive statewide environmental health screening tool, called CalEnviroScreen.

The top three places on the list of polluted ZIP Codes were all in the San Joaquin Valley: Fresno, Bakersfield and Stockton. In fact, two of the most polluted ZIP Codes were in Fresno and three were in Stockton.


The most polluted ZIP Code in Southern California was in Vernon, a city of only about 100 residents composed almost entirely of factories and other businesses, at No. 4. Also in the top 10 were Baldwin Park at No. 7 and unincorporated East Los Angeles at No. 8.

Sam Delson, a spokesman for the state’s EPA, said the study encompassed 1,769 ZIP Codes, looking at things such as pesticide use, traffic density and groundwater pollution. He said the agency hopes the study will result in investments to tackle the problem in the most pollution-burdened communities.

“CalEnviroScreen represents an important step in honoring our commitment to address environmental justice issues for the benefit of all of California’s communities and residents,” said Arsenio Mataka, the EPA’s assistant secretary for environmental justice.

Every major region of the state except the rural northern parts of California had some communities that were ranked among the highest 10% for combined “vulnerabilities from pollution,” according to the EPA.

Overall, about half the ZIP Codes that ranked in the top 10% for pollution in the state are in the greater L.A. area, Delson said, including the Inland Empire.

“Some people expected most of these ZIP Codes to be in industrial, urban areas,” Delson said Wednesday. “It was surprising to some that while many were in urban areas, a lot of them were in agricultural areas.”